Ball hone advice.

[Krooser]

I'm going to hone one cylinder of a late model Hemi I have in my shop... one piston was scuffed.

What do you suggest for hone material and grit? I'm using a stock Mopar poston and ring...Mahle I believe.

[hoodeng]

Ball hones are really only good for changing the texture of the bore surface for easier ring seating ,they can not correct or alter a bores geometry.
If you have a scuffed piston out of the bore you are servicing, it may have left a rub or slight distortion that only a rigid hone can correct.

Scuffing can also leave a metal transfer on the bore wall that only a rigid hone will clean off. I have know people to get into a bore with abrasive paper etc to clean up metal transfer then ball hone ,all they have done is make it look good , how accurate the bore is is another matter.

Cheers.

[user-30257]

I'm going to hone one cylinder of a late model Hemi I have in my shop... one piston was scuffed.

What do you suggest for hone material and grit? I'm using a stock Mopar poston and ring...Mahle I believe.

I'd suggest bringing it to a machine shop, and spending less on having it done properly, than spending more and ruining the bore.. Unless you have a portable AN style hone, you will most likely do nothing with a ball hone.

[Newold1]

hoodeng

X2 Great Answer!

[Krooser]

Duplicate

[Krooser]

I have a rigid hone but I figured a ball hone would be sufficient to do the job.

The cylinder in question is in a low mileage block in a car that was ditched and ran a bit before being shut off... The crosshatch us still there but I can feel a few very very tiny bits of what I think is aluminum. Nothing you can catch a nail on.

I talked to a trusted shop and he told me I have nothing to lose using a ball hone. I don't even want to pull the crank out of the block. I figure three or four passes with the hone will do the trick.

[Dutchman]

Bore gauges don't lie. People do

[groberts101]

I think these guys are right on target. That looks like far more than metal transfer to me. Even with lack of any nail catching score marks, looks like it wiped the cross hatch out completely.

So unless you run a pretty aggressive ball hone in it before finishing off with a finer grit?.. doesn't look like your going to be able to restore the cross hatch to help control oil and blowby.

[Hrdlx62]

That looks like rigid hone territory. Try a bit of muratic acid on a swab to get the aluminum off. neutralize the area with some caustic soulution. Get rigid hone fired up and clean up the cylinder. If the hole cleans up in a couple thou it will be ok. If not, well that's what machine shops are for.

[mike hohnstein]

B lookin' for a .010 piston/ring set on that hole.

[1972ho]

Plus ball hones don’t take off material they are just used to deglaze the cylinder,check there websight.

[Tuner]

That looks like rigid hone territory. Try a bit of muratic acid on a swab to get the aluminum off. neutralize the area with some caustic soulution. Get rigid hone fired up and clean up the cylinder. If the hole cleans up in a couple thou it will be ok. If not, well that's what machine shops are for.

This^^^^ followed with this 400 sandpaper procedure below. Use the muratic acid to remove the aluminum and try the 400 paper first to see if you can avoid resorting to the rigid hone. If you can get a reasonable wall surface using just the acid and sandpaper you might get what you need without making the hole any bigger.

With a spring loaded three-legged trapezoid type “glaze breaker” hone put duct tape sticky side out over the stones (do a good job of securing the tape behind the stones) and use 400 wet-or-dry paper to polish the cylinders. Put the paper in the cylinder first and let the hone expand into it so the paper sticks to the duct tape. If the cylinder is large, a sheet of paper may have to be cut in half and the haves offset to get full coverage on all three stones. The two pieces have to be overlapped the right direction so they don’t act like a sprag. One way they trail and turn easily and the other they wedge up and jam. Use a ¼ or 3/8 drill motor and trickle water from a hose while you polish. WD 40 is OK but it’s messier and you have to wash with water in the end anyway. A trickle of water flushes the trash away and the paper doesn’t load up as quick. Stroke up and down to generally follow the existing cross-hatch scratches. If you have the patience for it, follow the 400 with 600 and 1000 paper. Naturally, you have to be careful not to tear the paper or let the stones touch the wall and scratch it. I don’t think the walls can be made smooth enough.

400 paper will polish the walls and achieve the “plateau finish” that has been the subject of a lot of mumble over the years and won’t remove enough material to eliminate the crosshatch marks of the stone hone job so there will still be enough oil to keep the “don’t make it too smooth” crowd happy. The surface of the moly ring is full of microscopic fractures that are where the oil molecules hang out, so the wall doesn’t have to be rough.

This is the exact process that Glidden and the every other Pro Stock engine builder I know are using with the ultra tiny, super thin rings with PVD-Moly face. Most stop with the 600 grit paper. Most hard core SS/ and Stocker racers have done this for as long as I can remember. We abandon it for a long time but came back to it when it proved to be better in testing. Its funny how things come full circle. The penny trick I have not heard of. I will try that.

[Krooser]

We'll see how this goes...it really looks worse in the photo than it is in person. You can still see the cross hatch throughout the entire cylinder...the tiny beads of aluminum sit on top of the cross hatch.

I ordered a 400 grit flex hone today... Got my other hone on standby. Still have some muriatic acid left from my shop floor coating deal from 15 years ago.

I was going to cheapen out and order a no name piston but I think a new Mopar piston/ring/conrod assembly is a good deal at around $145.00.

Film at 11...

[jed]

Not the best fix but will probably work better than we all expect.
Please let us know how it turns out.
John

[Krooser]

I will Jed...